Supplying yarn



Nov. 13, 1951 E. J. ABBOTT 2,574,455

SUPPLYING YARN Filed June 8, 1948 fweniar ward 'effl i M zZMAW/W Patented Nov. 13, 1951 SUPPLYING YARN Edward J. Abbott, Wilton, N. IL, assignor, by mesne assignments, to Abbott Worsted Mills, Incorporated, Wilton, N. IL, a corporation of New Hampshire Application June 8, 1948, Serial No. 31,643

22 Claims.

This invention relates to supplying yarn and is more particularly concerned with holding yarn while the yarn is being progressively drawn off or away from a place of supply, by a yarn treating or using device. The invention is of wide utility in various situations in retaining yarn in arrangement for drawing off, such as situations in which the yarn to be drawn off is of relatively small amount, or the yarn has been drawn off down to a relatively small amount, or when the yarn to be drawn off is a remnant or a residue from previous drawing off, or when a package or mass of yarn to be drawn off is not sulliciently self-sustainin'g'or form-retaining to retain its yarn in proper position for drawing off, either because of the manner of its preparation or because it is nearly exhausted. Again,

' the invention is useful where yarn of a package is to be held in shape by a force, such as centrifugal force, which may need to be, or is, withdrawn or terminated before the drawing off of yarn is completed, and which therefore ceases to hold the package in shape.

The invention is applicable to these and other situations and various combinations of these situations, and by way of example, the invention will be explained as applied to the drawing off of filament yarn from a hollow cake. Such hollow cake is the typical package in which filament yarn is collected in a spinning cup during its manufacture.

Such a cake is usually deficient in self-sustaining or form-retaining characteristics, the coils of filament yarn which make up the cake are liable to slip off either from the outside or from the inside, and it is customary to hold such a cake together and protect it during handling by use of a fabric cover. This cover may be a tube of somewhat stretchable fabric which may be inserted through the interior hole of the cake and turned over at the top and bottom so as to cover the outside of the cake.

n drawing off yarn from such a cake, for instance in rewinding the yarn into the form of a cone or cheese, the cake and its fabric cover may be slipped onto a spindle or plug which fills the interior hole of the cake and keeps the cake generally circular in shape, and the fabric cover may then be laid back to expose the outside of the cake, the upper part of the fabric cover being held out of the way for instance by tucking it down inside a hollow part of the spindle or plug. The filament yarn can then be unwound from the outside of the cake, the unwinding progresslng inwardly. The unwinding operation generally proceeds fairly satisfactorily until the yarn of the cake has been largely drawn off, but when the wall of the cake becomes thin and the yarn near and at the fabric lining is being unwound, considerable breakage occurs.

The cake, with its fabric lining removed, could be unwound from its interior outwardly, but at the stage when the wall of such a cake becomes thin it tends to collapse and the residue of yarn entangles.

The invention will be explained by way of example, as applied to the drawing off of yarn from such cakes, and it will be apparent that the invention avoids the disadvantages and difflculties mentioned above, and provides a substantial improvement in supplying yarn to yarn treating or yarn using mechanism generally.

In the drawings,

Fig. 1 is a schematic view largely in vertical section, of one form of apparatus suitable for practice of the present invention;

Fig. 2 is a similar view showing only a small quantity of yarn yet remaining to be withdrawn, and

Fig. 3 is a diagrammatic view of the head of a winding machine, illustrative of yarn treating or using mechanism adapted to draw off the yarn.

The head of the winding unit shown in Fig. 3, is illustrated merely to show one possible device for drawing away the yarn, either continuously or discontinuously, and is shown as including a rotary tractor roll ll driving a winding cone l2 of yarn while a reciprocating thread guide l3 distributes the yarn :1 on the cone in a regular pattern.

In the illustrated form of the invention the yarn, in preparation for being drawn off, is shown as held against previous support by differential air pressure.

Thus the cake 20, without any cover, is held in a holder shaped as a cup 2| having an annular perforated side wall 22. A casing 25 surrounding the perforated side wall, but leaving the top of the cup open, is connected through pipe 21 and valve 28 to any suitable vacuum pump or fan, not shown, adapted to maintain subatmospheric pressure in the casing 25. A differential of air pressure is thus created. the pressure being higher at the inner surface of the cake and lower at the exterior periphery of the cake.

The casing may extend to surround other similar s'ups, or may be connected to other similar casings each surrounding such a cup.

The perforated side wall 22 constitutes a pervious support for yarn to be drawn off, and the yarn of the cake 20 itself is a pervious body and affords pervious support to the yarn being drawn off, so that the differential of air pressure which exists between the inner surface of the cake and the casing 25 outside the perforated wall 22, increases the compactness of the cake and holds each convolution of the yarn against a perforate support or backing.

The differential of pressure and resulting radial flow of air from the interior of the cake through the body of the cake and through the perforated wall 22 prevents slipping or displacement of the convolutions.

Fig. 2 shows the especial utility of the invention in dealing with small amounts of yarn. This figure shows the cake of Fig. 1 almost exhausted by withdrawal of yarn therefrom, so that only a few convolutions are left, such few convolutions being almost certain to become displaced and tangle in the absence of some holding force. The differential air pressure however is adapted to hold these convolutions firmly against the pervious support afforded by the cup, and so prevent entanglement.

The differential pressure may be maintained throughout the drawing off. Or, when a package to be unwound, such for example as the cake 20, is sufficiently self-sustaining or form-retaining at least during initial stages of unwiding, application of the differential pressure can be delayed until the package is partly unwound. For example, in some cases suction need not be applied until near the end of the unwinding when the tendency of the convolutions of the package to become displaced is greatest.

It may be desirable to rotate the unwinding package, such as the cake 20, during the drawing oil of the yarn, thus applying an additional amount of twist to the yarn. For this purpose the cup 2| may be fast on a central shaft 30 which extends through a packing gland 3! in the casing 25 and is connected as by gearing 32, 33 to a driven shaft 34 rotating in synchronism with the driving element of the winding mechanism such as the tractor roll II. In this way the cup and its contained package may be rotated at high speed, applying twist to the yarn during the drawing off. At high speeds of rotation the centrifugal force tends to hold each convolution of the yarn of the package against underlying convolutions and against the wall of the cup, and in such case the centrifugal force may replace the differential in air pressure and render such differential unnecessary during continuance of the fast rotation of the package.

It is however occasionally necessary to stop the rotation of the package or packages in mechanism of this type before complete exhaustion of the yarn, for instance in order to repair a broken yarn, in order to replace a fully wound cone H of yarn on the winder with an empty cone, or in order to shut down the operation of the machine as a whole.

Preparatory t such stoppage of rotation, the suction may be applied by opening the valve 28, establishing the differential of pressure between the unwinding surface of the package and the casing 25. Then when rotation is stopped this differential of pressure will hold the yarn effectively in place until high speed rotation has again started, when the suction may be turned off.

It will be apparent from this explanation of an example of the invention that the form or shape of the perforate support for the yarn may be varied to suit the quantity of yarn to be drawn off or the shape of a package or body of the yarn, and to suit the direction of drawing off and the manner is which a package or mass of yarn diminishes as the yarn is drawn off.

Where this application refers to a layer or a support as underlying, it is meant that such layer or support is itself overlaid or covered by yarn, but such layer or support is not necessarily physically lower than such overlying or covering yarn.

I claim: I

1. Method of supplying a yarn comprising holding the yarn against a pervious support by differential air pressure while drawing off the yarn.

2. Method of supplying a yarn comprising maintaining a flow of air through a pervious support in a direction to urge the yarn against said support while drawing off the yarn.

3. Method of supplying a yarn comprising retaining the yarn in arrangement for drawing off by establishing suction at one side of a pervious support to hold the yarn against the opposite side of said support.

4. Method of supplying a yarn comprising supporting a package of yarn in position for progressive withdrawal of its yarn from a given surface of the pacakage, and increasing the compactness of the yarn forming said surface by establishing a differential of a r pressure between said surface and a further surface of the package, with the lower pressure at said further surface.

5. Method of removing yarn from a package comprising drawing off yarn from a surface of the package while holding the yarn forming said surface against underlying yarn of the package by differential air pressure.

6. Method of removing yarn from the interior 'of a package comprising drawing off yarn from an interior surface of the package while holding the yarn forming said surface against underlying yarn of the package by differential air pressure.

'7. A method of removing yarn from a package comprising drawing off yarn from an exposed layer of the package while holding such exposed layer against an underlying layer by differential air pressure.

8. Method of removing yarn from a package comprising drawing off yarn from a surface of the package while holding the yarn forming said surface against underlying support by differential air pressure.

9. Method of supplying a yarn comprising supporting a package of yarn in position for progressive withdrawal of its yarn from an interior surface of .the package, and preventing collapse of convolutions of the yarn defining said interior surface by causing a flow of air to enter the body of the package through said interior surface and pass through the package.

10. Method of supplying a yarn comprising supporting a package of yarn in position for progressive withdrawal of its yarn from an interior surface of the package, and preventing collapse of convolutions of the yarn defining said interior surface by causing a flow of air to pass radially through the package from said interior surface outwardly.

11. Method of removing yarn from a package comprising drawing off yarn from a surface of the package and forcing the yarn against said surface preparatory to such drawing off by maintaining a differential in air pressure between said surface and a further surface of the package, with the lower pressure at said further surface.

12. Method of removing yarn from a package comprising drawing off yarn from a surface of the package while urging the body of yarn of the package against a pervious support by diflerential air pressure.

13. A method of unwinding a yarn package consisting of supporting the yarn package and unwinding the package by drawing yarn from the surface most remote from the support while subjecting the diminishing package to a differential of air pressure wherein the lower pressure exists at the support.

14. A method of unwinding yarn from a package comprising supporting the package, drawing yarn from the package so as to diminish the yarn package toward the support, and when the residue consists of but a few layers holding the residual layers against the support by differential air pressure.

15. A method of unwinding yarn from a package by supporting the package within a perforated holder. drawing yam from an interior surface of the package so as to diminish the package toward the wall of the holder, and when the residual yarn of the package consists of but a few layers, holding such residual yarn against the wall of the holder by differential air pressure.

16. A method of unwinding yarn from a package thereof comprising rotating the package about its axis, drawing yarn from an interior surface thereof during rotation thereof, and during stoppage of rotation of the package prior to exhaustion of the yarn, subjecting the residual yarn of the package to a differential of air pressure wherein the higher pressure is at said interior surface.

17. In combination with a device arranged to draw yarn away from a place of supply, a perforate backing against which a yarn is adapted to lie, and a suction connection connecting one side of said perforate backing to a source of suction and arranged to apply differential air pressure to retain the yarn in place against the op-' posite side of said backing pending withdrawal thereof by said device.

18. In combination with a device arranged to draw yarn away from a place of supply, a container adapted to confine a body of yarn, said container having a perforate wall, the perforations leading to the yarn body, and means for applying suction to the container to provide a flow of air from a free surface of the body of yarn through said body and through said perforate wall, thereby to retain the yarn of the body in place pending withdrawal thereof by said device.

19. Apparatus for unwinding a package of yarn comprising a support having a perforated wall with which a surface of the package is engaged, means for drawing yarn from a surface of the package which is not in contact with the perforated wall to diminish the package toward said wall, and means for establishing a difierential air pressure, with the lower pressure on the side of the wall opposite the side with which the package is in contact and with the higher pressure at the surface from which yarn is drawn.

20. Apparatus for unwinding a package of yarn comprising a supporting cup having a perforated peripheral wall, within which the yarn package is disposed with its outer surface adjacent to the perforated wall, means for drawing yarn from the interior of the package to diminish the package toward the wall, and means for establishing a differential air pressure, with the lower pressure outside of the perforated wall and with the higher pressure at the surface from which yarn is drawn.

21. Apparatus for unwinding a package of yarn comprising a supporting cup having an open top and a perforated peripheral wall within which the yarn package is disposed with its outer surface adjacent the perforated wall, a housing around said perforate wall but exposing the open top of the cup, means for drawing yarn from the interior of the package through the open top of the cup to diminish the package toward the perforated wall, and means for maintaining a subatmospheric pressure within the housing.

22. Apparatus for unwinding a package of yarn comprising a support having a perforated wall with which a surface of the package is en aged, means for rotating the support, means for drawing yarn from a surface of the package which is not in contact with the support to diminish the package toward the wall thereof during rotation, and means for establishing a differential air pressure, with the lower pressure existing at the side of the wall which is not in contact with the package and with the higher pressure at the surface from which yarn is withdrawn.

EDWARD J. ABBOTT.

REFERENCES CITED The following references are of record in the Date 512,502 Germany Nov. 12. 1930 

